Stone fragment suction device

ABSTRACT

Methods and apparatus for a stone fragment suction device. An apparatus includes a steerable access sheath having a proximal end and a distal end, a tip at the distal end, and a suction conduit positioned within a central lumen of the steerable access sheath from the distal end to the proximal end, the steerable access sheath containing an outer lumen surrounding the central lumen with one or more channels therethrough, an outer circumference of the outer lumen and an outer circumference of the central lumen forming concentric circles, the steerable access sheath further including a radiopaque material at the distal end or along a length of the steerable access sheath to enable tracking with a remote fluoroscopic device.

BACKGROUND OF THE INVENTION

The present invention generally relates to a kidney device, and morespecifically to a stone fragment suction device.

In general, one purpose of a human kidney is to filter waste productsfrom the blood and excrete these substances and excess water in the formof urine. A calyx section of the kidney generally refers to a beginningof the urine collecting system. A kidney typically has 6-10 calyces.Stones in the kidney are typically found within the calyx. In general, astone is a microscopic organized aggregation of salts. Procedures totreat the presence of kidney stones include, for example, lithotripsyand ureteroscopy.

Ureteroscopy is a practice used to diagnose the presence of kidneystones or to provide access for other devices such as lithotripters,graspers, or stone baskets. Small stones have been treated with only astent (no lithotripsy), by dilating the ureter. However, if the stone islarge, continues to cause problems, or the urinary system appearsinfected, a urologist may elect to perform a procedure during which anendoscope is used to place a small tube in the ureter. This small tubeallows urine to pass, which can alleviate pain, and dilates the ureter,allowing small stones to pass.

Treatment of kidney stones with ureteroscopic lithotripsy or laserfibers creates stone fragments and stone dust or “sand.” Stone basketsor graspers may have problems removing stone fragments that are below 2mm in size. When small stones and stone dust are present in the moredifficult to access calyces of the kidney, it would be desirable to havea more robust removal mechanism. In these cases, unless the small stonesand stone dust are removed, they can continue to grow and aggregateuntil they become symptomatic and require more invasive treatment.

Therefore, what is needed is a device and method of mechanicallyremoving kidney stone fragments and stone dust or “sand” in order toreliably reduce the amount of fragmented kidney stones left in apatient, particularly following treatment with ureteroscopic lithotripsyor laser fibers.

SUMMARY OF THE INVENTION

The following presents a summary of the innovation in order to provide abasic understanding of some aspects of the invention.

The present invention provides methods and apparatus for a stonefragment suction device.

In general, in one aspect, the invention features an apparatus includinga steerable access sheath having a proximal end and a distal end, a tipat the distal end, and a suction conduit positioned within a centrallumen of the steerable access sheath from the distal end to the proximalend, the steerable access sheath containing an outer lumen surroundingthe central lumen with one or more channels therethrough, an outercircumference of the outer lumen and an outer circumference of thecentral lumen forming concentric circles, and the steerable accesssheath further including a radiopaque material at the distal end oralong a length of the steerable access sheath to enable tracking with aremote fluoroscopic device. In other embodiments, the central lumen isprovided offset from a central longitudinal axis of the outer lumen oras a noncircular shaped channel, for example with an ovular crosssection. An ovular cross section may be desirable to provide moresurface area while staying within certain guidelines for Fr (French)size in order to fit within an endoscope. It is further contemplatedthat the device may be used independent of an endoscope and may have alarger diameter as a result.

Embodiments of the invention may have one or more of the followingadvantages.

The apparatus of the present invention provides a mechanical means ofremoving sand and small fragments of kidney stones without the need ofbaskets.

The apparatus of the present invention reduces the amount of fragmentedkidney stones left in a patient.

The apparatus of the present invention may eliminate the need for directvisualization of a suction device and the materials it is removing andaccommodates fluoroscopic evaluation by employing a radiopaque materialin a tip or through a body of the apparatus. By incorporating theradiopaque material in the tip or through the body of the apparatus, auser can locate a suction device within a patient without directvisualization.

The apparatus of the present invention may include a suction conduitconfigured in different diameters along its length to minimize theincidence or frequency of fragments from becoming lodged within thesuction conduit. For example, the suction conduit may be narrower at adistal end and widen toward a proximal end.

The apparatus of the present invention may include a fluid outflow linewhich may be designed to target equal fluid outflow and suction inflowto prevent or limit the potential for pressure drops or collapses in akidney during use.

The apparatus of the present invention may include a clear section onthe suction conduit to enable visual confirmation of sand and fragmentremoval. This clear section can be configured as a chamber and includeone or more particle filters to enable sand and fragment quantificationand collection. The clear section may help indicate to a user if thesuction conduit is clogged.

Accordingly, pursuant to one aspect of the present invention, there iscontemplated an apparatus comprising a steerable access sheath having aproximal end and a distal end; a tip at the distal end; and a suctionconduit positioned within a central lumen of the steerable access sheathfrom the distal end to the proximal end, the steerable access sheathcontaining an outer lumen surrounding the central lumen with one or morechannels therethrough, an outer circumference of the outer lumen and anouter circumference of the central lumen forming concentric circles, thesteerable access sheath further comprising a radiopaque material at thedistal end or along a length of the steerable access sheath to enabletracking with a remote fluoroscopic device.

The invention may be further characterized by one or any combination ofthe features described herein, such as the tip further comprises achamfered and soft edge for ease of insertion, the chamfered edgecomprises a restricted opening, the suction conduit is tapered withdecreasing diameters from the proximal end to the distal end of thesteerable access sheath, the suction conduit is configured to generateturbulence, the suction conduit is configured to enable alternating adirection of fluid flow, a fluid inflow channel positioned within thesteerable access sheath from the distal end to the proximal end, thefluid inflow channel is configured to collapse when there is no fluidinflow, the tip is selectively deflectable to enable specific placementof the suction conduit, the suction conduit comprises a steeringmechanism selected from the group consisting of one or more cables and alockable control actuator, the steerable access sheath further comprisesan anchoring mechanism to prevent a migration of the steerable accesssheath during active suction, the anchoring mechanism is a fluid inflowchannel, the anchoring mechanism is positioned along a length of thesteerable access sheath, the anchoring mechanism is selected from thegroup consisting of an inflation balloon and one or more retractabletines, the suction conduit comprises a clear section to enable visualconfirmation of continued sand and fragment removal, the clear sectioncomprises a chamber having a particle filter to enable quantificationand collection of sand and fragments, the suction conduit comprises aport sealed around an introducer configured to agitate the suctionconduit, a channel positioned within the outer lumen of the steerableaccess sheath from the distal end to the proximal end; and one or morefiberoptic imaging fibers positioned within a length of the lumen.

Accordingly, pursuant to another aspect of the present invention, thereis contemplated an apparatus comprising an access sheath having aproximal end and a distal end; a tip at the distal end; and a suctionconduit positioned within a central lumen of the access sheath from thedistal end to the proximal end, the access sheath containing an outerlumen surrounding the central lumen with one or more channelstherethrough, the access sheath further comprising a radiopaque materialat the distal end or along a length of the access sheath to enabletracking with a remote fluoroscopic device, wherein the suction conduitcomprises at least half the volume of the access sheath.

Accordingly, pursuant to another aspect of the present invention, thereis contemplated an apparatus comprising an access sheath having aproximal end and a distal end; a tip at the distal end; and a suctionconduit positioned within a central lumen of the access sheath from thedistal end to the proximal end, the access sheath containing an outerlumen surrounding the central lumen with one or more channelstherethrough, the access sheath further comprising a radiopaque materialat the distal end or along a length of the access sheath to enabletracking with a remote fluoroscopic device, wherein the access sheathhas a preformed tip angle.

These and other features and advantages will be apparent from a readingof the following detailed description and a review of the associateddrawings. It is to be understood that both the foregoing generaldescription and the following detailed description are explanatory onlyand are not restrictive of aspects as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood by reference to the detaileddescription, in conjunction with the following figures, wherein:

FIG. 1 is a side elevation view of a first exemplary stone fragmentsuction device of the present invention.

FIG. 2 is a sectional view taken along line 5-5 in FIG. 1.

FIG. 3 is a side elevation view of a second exemplary stone fragmentsuction device of the present invention.

FIG. 4 is a sectional view taken along line 105-105 in FIG. 3.

FIG. 5 is a cross section of an exemplary suction conduit of the presentinvention.

FIG. 6A is a side view of an embodiment of the present invention beingmanipulated within a patient's anatomy.

FIG. 6B is a side view of an embodiment of the present invention beingmanipulated within a patient's anatomy.

FIG. 6C is a side view of an embodiment of the present invention beingmanipulated within a patient's anatomy.

FIG. 7 is a cross sectional view of an embodiment of the presentinvention.

FIG. 8 is a side view of an embodiment of the present invention.

FIGS. 9A-9C are cross-sectional views of embodiments of the presentinvention that target different exit angles for directed fluid flow.

FIGS. 9D-9E are side views of embodiments of the present invention thattarget different exit angles for directed fluid flow.

FIG. 10 is a side view of an embodiment of the present invention.

FIG. 11 a is a side view of an embodiment of the present invention.

FIG. 11 b is a side view of an embodiment of the present invention.

FIG. 12 is a cross sectional view of an embodiment of the presentinvention.

FIG. 13 is a cross sectional view of an embodiment of the presentinvention.

FIG. 14 is a cross sectional view of an embodiment of the presentinvention.

FIG. 15 is a perspective view of an embodiment of the present invention.

FIG. 16 is a perspective view of an embodiment of the present invention.

FIG. 17 is a perspective view of an embodiment of the present invention.

DETAILED DESCRIPTION

The subject innovation is now described with reference to the drawings,wherein like reference numerals are used to refer to like elementsthroughout. In the following description, for purposes of explanation,numerous specific details are set forth in order to provide a thoroughunderstanding of the present invention. It may be evident, however, thatthe present invention may be practiced without some of these specificdetails. In other instances, well-known structures and devices are shownin block diagram form in order to facilitate describing the presentinvention.

As shown in FIG. 1, a first exemplary stone fragment suction device 10includes a steerable access sheath 15 having a proximal end 20 and adistal end 25. The distal end 25 includes a tip section 30.

The tip section 30 may be configured with a chamfered and soft edge forease of insertion into the ureteral orifice of a human kidney. In onespecific embodiment, the chamfered edge and soft edge of the tip section30 includes a restricted opening. It is contemplated that the tip of thestone fragment suction device 10 may further comprise a preformed tipangle. Such a preformed tip angle would allow passive steering throughrotation of the stone fragment suction device 10. Rotating the stonefragment suction device about the longitudinal axis would allow thepreformed angle at the tip to rotate to different positions about thelongitudinal axis and this may help to navigate through and intodifficult to reach locations. The combination of rotation of thepreformed tip angle and use of active deflection may facilitate easiernavigation through tortuous pathways.

The stone fragment suction device 10 may include a radiopaque materialat a tip section 30 or along its length that enables a user to identifya location of the stone fragment suction device 10 relative to apatient's body using fluoroscopic techniques.

The proximal end 20 may include a suction connection 35. The suctionconnection 35 is configured to provide a connection of the proximal end20 of the steerable access sheath 15 to a suction plug (not shown) or aremovable suction receptacle (not shown). The removable suctionreceptacle enables a collection of materials suctioned through a suctionconduit, fully described below. The removable suction receptacle may beequipped with a disconnectable filter used to separate particles ofdifferent sizes within the removable suction receptacle to more easilyfacilitate stone pathology analysis. It is contemplated that the suctionconduit may also function as an irrigation channel and one channel maybe interchangeably used for both purposes. It is contemplated that itmay be desirable to monitor the fluid outflow into the patient and thefluid inflow out of the patient to ensure that excess fluid is not leftwithin a patient's kidney or that excess fluid is removed.

As shown in FIG. 2, extending longitudinally through the steerableaccess sheath 15 from the distal end 25 to the proximal end 20 is asuction conduit 40 positioned within a central lumen 45. It iscontemplated that the size of the suction conduit may be variabledepending on whether or not the internal fluid channel is in an expandedor contracted state. When fluid is actively flowing through the internalfluid channel, which may be positioned within central lumen 45, internalfluid channel may expand to allow fluid to flow along the length.Internal fluid channel may be made of compressible material, materialthat folds over itself, stretchable material, or the like. When internalfluid channel is not in active use (i.e. no fluid flow), internal fluidchannel may enter a contracted state allowing central lumen 45 moresurface area for active suction of stone particles and stone debris. Itis contemplated that the size of the suction conduit may be variablealong the length of the ureteral access sheath. It is contemplated thatthe suction conduit may comprise greater than 50% of the total volume ofthe ureteral access sheath or less than 50% of the total volume of theureteral access sheath, preferably greater than 50% of the total volumeof the ureteral access sheath to allow for passage of larger stones. Thesteerable access sheath 15 also includes an outer lumen 50 surroundingthe central lumen 45 and containing one or more channels 55, 60therethrough. While this embodiment is shown to include two channels 55,60, other embodiments may include additional channels within the outerlumen 50.

In one embodiment, the suction conduit 40 is tapered with decreasingdiameters from the proximal end 20 to the distal end 25 of the steerableaccess sheath 15. This tapering of the suction conduit 40 minimizes apotential for stone fragments being lodged within the suction conduit40.

As shown in FIG. 3, a cross section of a second exemplary stone fragmentsuction device 100 includes a steerable access sheath 105 having aproximal end 110 and a distal end 115. The distal end 115 includes a tipsection 120. The tip section 120 includes a radiopaque material thatenables a user to identify a suction device as well as the tip section's120 location relative to a patient's body using fluoroscopic techniques.

The proximal end 110 includes a suction connection 125 adapted toreceive a removable suction plug 130 or sample jar (not shown). Anoptional adapter 135 and an inflow adapter 140 are positioned onapproximately opposite sides of the steerable access sheath 105 near theproximal end 110. Both adapters 135, 140 enable an introduction offluid, steering mechanisms, and other materials, through channels 136,137, respectively.

Optionally, anterior to the optional adapter 135 and an inflow adapter140 there is a steering mechanism 145 surrounding the steerable accesssheath 105. In some embodiments, also included on the steerable accesssheath 105 is an anchoring device 150, such as, for example, aninflation balloon, one or more retractable tines, a fixed spiral, aninflatable spiral, a spiral which may be driven under power, and soforth. Spiral technology used for this purpose is taught in U.S. Pat.No. 5,601,537, the contents of which are incorporated by reference intheir entirety. The anchoring device may be located at a distal regionof the device, located along the length of the device, or both. Theanchoring device 150 may be used to prevent migration of the steerableaccess sheath 105 during an active suction procedure. In the case wherethe anchoring mechanism is a power spiral, a fixed spiral, or aninflatable spiral, the spiral may be used to move the access sheath intoposition through the tortuous pathways within an anatomical region ofinterest.

As shown in FIG. 4, extending longitudinally through the steerableaccess sheath 100 along line 105-105 from the distal end 115 to theproximal end 110 is a suction conduit 155 positioned within a centrallumen 160. In an embodiment, the suction conduit 155 includes a clearsection to enable visual confirmation/observation of sand and fragmentremoval. This clear section may include a chamber housing a particlefilter to enable quantification and collection of sand and fragments.The steerable access sheath 105 also includes an outer lumen 165surrounding the central lumen 160 with one or more channels 170, 175therethrough. While this embodiment is shown to include two channels170, 175, other embodiments may include one or more additional channelswithin the outer lumen 165.

In one example, channel 170 is a fluid inflow channel connected to theinflow adapter 140 that provides a link to an external source of fluid(not shown). In an embodiment, this fluid outflow channel 170 isconfigured to collapse when there is no fluid flow. In anotherembodiment, the fluid inflow channel is a flexible tube expandable intothe suction conduit 155 during active fluid infusion.

In one embodiment, an internal portion of the fluid inflow channel 170is rigid. In another embodiment, the internal portion of the fluidinflow channel 170 may expand radially during active fluid flow. In someembodiments, the fluid inflow channel may be in one or multiple lumensand may be within another lumen internal to the suction conduit 155.

In still another embodiment, only a proximal portion of the suctionconduit 155 is selectively collapsed, pinched off, or incorporates amechanism for halting or reducing suction flow such that the fluidinflow channel 170 is used to temporarily increase pressure or distendthe distal portion of the suction conduit 155 to free fragments that maybecome lodged in the suction conduit 155. In one particular embodiment,the suction conduit 155 is designed to permit alternating a direction offluid flow.

In another embodiment, since a human kidney is susceptible to bothhigher and lower pressures, the suction conduit 155 includes a closedloop design to keep a pressure ratio between inflow and outflow volumeclose to one. In some embodiments, this may involve the use of afeedback mechanism and/or a user display indicating volume of fluid inand volume of fluid out. It is contemplated that a pressure sensor maybe located in the distal region of the tip of the suction conduit orouter sheath.

Incorporation of another channel in the outer lumen 165 surrounding thecentral lumen 160 provides an additional port enabling a user toselectively add other liquids to the fluid inflow channel 170, which islinked to the channel 137 of the inflow adapter 140. This may beadvantageous for the inclusion of materials such as those used influoroscopic contrast. In some applications, as vacuuming progresses, auser may introduce contrast to the inflow to better identify a locationof any remaining stones or sand.

In one embodiment, fiberoptic imaging in the form of fiberoptic andillumination bundles are included in channel 175. The fiberoptic andillumination bundles can include, for example, separate fibers or bemultiplexed on the same fibers.

Referring again to FIG. 3, in an illustrative embodiment, the tipsection 120 has a chamfered and soft edge for ease of insertion. Thechamfer may also provide a restricted opening, either by step down insize or some form of grill, to the suction conduit 155. In an alternateembodiment, the chamfered edge of the tip section 120 may have no effecton the suction conduit 155 while another form of suction conduit 155step down or restriction is included.

The suction conduit 155 may be constructed to have different diametersalong its length. For example, the diameters of the suction conduit 155can decrease from a larger diameter in a ureterovesical junction to asmaller diameter in the distal portion 115 of the suction conduit 155.This configuration minimizes a potential for fragments being jammed asthey enter the suction conduit 155 at the tip section 120.

In one embodiment, the fluid inflow channel 170 and suction conduit 155are configured to create turbulence or a vortex to improve stone removalperformance. It is contemplated that the addition of a syringe oralternative device to create force and provide faster fluid outflowspeeds may be desirable in the creation of turbulence or a vortex withinthe kidney. The turbulence or vortex may stir up stone fragments orstone dust which may help in flushing out the kidney. Targeted exitconduits provided in the present invention may be able to betterconcentrate inflow liquid on the far side of a stone burden from theoutflow orifice and thus more easily directly “wash” or “push” the stoneburden toward the outflow orifice.

Any removal of fluid from the ureter or calyx can cause a pressure dropand potentially collapse the kidneys, renal pelvis, ureter, calyx, andso forth. To overcome this, the fluid inflow channel 170 can be used tointroduce saline or other fluid to prevent such a collapse.

The suction conduit 155 can be used as a ureteral access sheath and havea large enough lumen to accommodate ureteroscopes. Typically, ureteralaccess sheaths are not advanced in a kidney beyond the ureteral pelvicjunction. Embodiments of the suction conduit 155 described herein,particularly those embodiments including a steering mechanism describedbelow, accommodate further advancement into the renal pelvis and majorcalyces to provide an effective stone fragment suction retrievalfunction.

As shown in FIG. 5, an exemplary stone fragment suction device 200 istubular in shape and includes a first portion 205 and a second portion210. The first portion 205 includes a tip section 215. Positioned withina length of the stone fragment suction device 200 from the tip section215 to a proximal end 220 is a pull cable 225. The second portion 210 isconstructed to be non-collapsible and semi-rigid and the first portion205 is constructed to be semi-flexible. The two portions 205, 210 enablethe tip section 215 to be controlled by the pull cable 225 by a flexingof the first portion 205 while not affecting the second portion 210.

The tip section 215 can be configured to be substantially straight orhave a preformed curve orientation. In some embodiments, the tip section215 is selectively deflectable to enable placement of working channelopenings directly opposite the lower poles of the kidney calyx. It iscontemplated that the first portion 205 may be a slotted or folded walltube section to enhance the flexibility of the distal end of the tubeand enable different configurations to be achieved such asomnidirectional bending or directional bending.

Although the stone fragment suction device 200 is shown with a singlepull cable 225, other embodiments include multiple pull cables and alockable control actuator to lock the tip section 215 at a desireddeflection angle. One or more pull cables or wires may be positionedwithin stone fragment suction device 200 for manipulating in one or moredirections. FIG. 8 illustrates an example of the device of the presentinvention provided with one pull cable 325. In this example, accesssheath 300 is provided with a preformed tip angle.

In some embodiments, it is contemplated that suction conduit 140 isnon-circular in cross section, for example slightly oblong or ovular, asshown in FIG. 7. It is contemplated that the outer diameter D2 of thesuction conduit 140 may be 11 or 12 Fr, ideally 12 Fr. It iscontemplated that the outer diameter D1 of the access sheath may be 13or 14 Fr. These sizes are chosen to be compatible with endoscopes orureteroscopes. It is contemplated that the access sheath of the presentinvention may be used independent of an endoscope. It is contemplatedthat additional channels, for example, one or more irrigation channels,one or more visualization channels, or one or more pull cable channelsmay be oriented toward one end of the access sheath. It is contemplatedthat channels other than suction conduit 140 may terminate before theextreme distal tip of the access sheath. For example, additionalchannels may terminate 0.2-1.5 cm before the extreme distal tip of theaccess sheath. This may provide for the addition of a flap, surfacedeflection, an angle formed into the distal end of the irrigationchannel, or otherwise add a directionality to the outflow of a fluidfrom the distal end of the irrigation supply channel.

FIGS. 6A-C and 7-8 illustrate access sheath 300 with a preformed tipangle being manipulated into different hard to reach calyces of thekidney. In one embodiment, far end 320 is abutted against a far wall ofthe calyx of the kidney. It is contemplated that irrigation fluid may bepassed through irrigation channel 305 in a directed outflow resulting inorganized fluid flow around the calyx in a direction 250, for example.This organized fluid flow direction 250 may help to clear small stones,stone fragments, or stone dust 260 by directing them toward the suctionconduit 140 where active suction helps to pull the small stones, stonefragments, or stone dust 260 to substantially clear them from thekidney.

FIGS. 9A-9E, 10 11A-11B, 12, and 13 illustrate distal end regions ofdifferent embodiments of irrigation tip portions of the steerable accesssheath of the present invention. Several targeted exit conduits 409,429, 449, 469, 489, and 529 are provided about a distal end region ofthe irrigation portions and may be oriented at different angles indifferent embodiments in order to create targeted flow to remove stonefragments or debris that might be stuck in a certain region of a kidneyfollowing fragmentation or lithotripsy. It is contemplated that throughthe design modifications of the present invention, flow may be directedwith the intent to move a stone burden (dust, debris) in a particulardirection, such as toward the exit of the kidney or toward the suctionorifice, for example at the distal end 25 of suction conduit 40.

Irrigation tip portions 400, 420, 440, 460, 480, 500, 520 and 540 areprovided with distal end 402, 422, 442, 462, 482, 502, 522, or 542 whichis soft, chamfered or curved as shown in 403, 423, 443, 463, 483, 503,523, and 543 for patient comfort during insertion. Walls 405, 425, 445,465, and 485 and contoured outermost edges 404, 424, 444, 464, 484, 504,524, and 544 of targeted exit conduits 409, 429, 449, 469, 489, and 529may be provided and arranged in order to facilitate the directionalityof the directed fluid flow.

In FIG. 9A, the one or more targeted exit conduits being orientedsubstantially orthogonal to the longitudinal axis of the steerableaccess sheath. In FIGS. 9B and 9D, the targeted flow direction isgenerally toward the proximal end of the device. FIG. 9B shows directionof flow 427 toward the proximal end along the longitudinal axis and FIG.9D shows direction of flow 467 angled proximally. In FIGS. 9C and 9E,the targeted flow direction is generally toward the distal end of thedevice. FIG. 9C shows direction of flow 447 toward the distal end alongthe longitudinal axis. FIG. 9E shows direction of fluid flow 487 angleddistally. Targeted flow channels may be provided along a single crosssectional plane as illustrated in FIGS. 9A-9D or along several crosssectional planes as in 9E to achieve the desired fluid flow velocity andcreate a desired turbulence effect to more effectively clean out stonedebris and stone dust from an anatomical region of interest, such as akidney. It is contemplated that fluid flow velocities from 25 to 250 mLper second would be well suited to this purpose. The fluid inflow mustmatch the fluid outflow or kidney damage due to positive/negativepressures may occur.

It is contemplated that the device of the present invention would betargeted at removing stone debris and stone dust that is less than about2 mm in diameter. Most preferably the device of the present inventionwould be capable of removing stone debris and stone dust that is largerthan 1 mm in diameter so as to eliminate the majority of debris and/ordust remaining following fragmentation or lithotripsy. It iscontemplated that fluid flow into the patient would travel through fluidflow channel 170, for example, and that targeted exit conduits would beconnected into the fluid flow channel such that fluid may exit equallyfrom all targeted exit points. It is further contemplated that flowmight be restricted in certain channels and unrestricted in otherchannels to further direct the flow. Subsequent suctioning to remove theoutflow of fluid into the patient and any stone dust or stone debris mayoccur through central lumen 40, 140, or 155, for example.

FIGS. 10-13 illustrate an alternative embodiment of the device of thepresent invention which is equipped with a mushroom shaped distal end.The mushroom shaped distal end 510, 530, and 550 are capable of forminginto a closed position during insertion or removal (FIG. 11B) whereinthe outside diameter of the device resulting from lateral protrusions508, 528, 548 is reduced and forming into an open position wherein thelateral protrusions are extended during active fluid flow, suction,and/or stone removal (FIGS. 10, 11A, and 12). It is contemplated thatseveral layers of polymer, silicone, or plasticized material formed intoflaps 531, for example, may be used to accomplish this result. It iscontemplated that the layers of material may be forced open by theactive fluid flow and return to a resting closed state when active fluidflow is not occurring. Additional features may be included in themushroom shaped head, including the targeted exit conduits shown inFIGS. 9A-9E, located at various positions through the mushroom shapedhead to preferentially direct the fluid flow. The mushroom head mayprovide a more effective proximally directed fluid flow than thetargeted exit conduits on their own. It is contemplated that applicationof some fluid pressure during insertion may keep the one or more inflowlumens inflated and stiff in their preferred orientation. Conversely, iflittle or no fluid inflow is provided during insertion, when inflowbegins it may be likely that the inflow lumens would inflate and deployand even if folded back a bit from insertion, the inflow lumens would beable to fully inflate and deploy.

FIG. 12 illustrates a cross sectional view of irrigation tip portion520, in which central lumen wall 521 supports mushroom shaped head 530within the outer wall of irrigation tip portion 520. Mushroom shapedhead 530 is supported within the access sheath main lumen withextensions 525. Gap 526 is provided at the base of mushroom shaped head530 to allow for the flow of fluid out from the device into a patient'sanatomy. It is contemplated that additional exit conduits may be placedat the distal most end 522 of the steerable access sheath to directfluid in line with the longitudinal axis of the access sheath.

FIG. 13 illustrates direction of fluid flow 527 which is targetedaxially around mushroom shaped head 530 through targeted exit conduits529 in irrigation tip portion 520. Fluid enters through central lumen532 into mushroom head and is distributed through targeted exit conduits529. Central lumen wall 532 may help to guide the fluid flow into thetargeted exit conduits 529.

FIGS. 14-17 illustrate how irrigation tip portion 400, 420, 440, 460,480, 500, 520, and 540 may be integrated into access sheath 10, 100,200, or 300. FIG. 14 illustrates irrigation tip portion 520 withmushroom shaped head 530 extending distally from fluid inflow channel170 to create a fluid flow path 527 which may help return stonefragments and stone debris to suction conduit 155.

FIG. 15 illustrates a plurality of irrigation tip portions 480protruding from a distal region of steerable access sheath 100. Targetedexit conduits 489 located toward a distal end of irrigation tip portions480 help guide fluid flow in direction 487 to create turbulence or avortex at the distal end of steerable access sheath 100. In thisembodiment, fluid flow is in a direction around and in front of the tipof the access sheath and active suction may help to draw stone debris orstone dust back into suction conduit 155 to remove it from a patient. Itis contemplated that irrigation tip portions 480 may be movable furtherinto and subsequently withdrawn from the distal end of steerable accesssheath 100. Movement of irrigation tip portions 480 may further aid instirring up debris to be removed from difficult to reach locations. Suchirrigation tips may have slight pre-existing bends for better steeringof tip into difficult to reach locations.

FIGS. 16 and 17 illustrate embodiments wherein irrigation portions 420and 520, respectively, are inserted within a central suction conduit asan accessory instrument. In this embodiment, stone fragment suctiondevice 200 is provided with control means at a proximal end foradvancing and retracting irrigation portions 420 and 520 as appropriateto encourage the creation of turbulence to remove stone fragments andstone debris. Typically irrigation portions 420 and 520 would bemaintained within the central suction lumen during insertion and removalof stone fragment suction device 200 into and out of a patient'stortuous anatomy. Mushroom shaped head 530 and targeted exit conduits429 help to encourage fluid flow back into central suction lumen tofacilitate removal of unwanted debris from a patient.

Some embodiments may be described using the expression “one embodiment”or “an embodiment” along with their derivatives. These terms mean that aparticular feature, structure, or characteristic described in connectionwith the embodiment is included in at least one embodiment. Theappearances of the phrase “in one embodiment” in various places in thespecification are not necessarily all referring to the same embodiment.

While this invention has been particularly shown and described withreferences to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of the presentapplication as defined by the appended claims. Such variations areintended to be covered by the scope of this present application. Assuch, the foregoing description of embodiments of the presentapplication is not intended to be limiting. Rather, any limitations tothe invention are presented in the following claims.

What is claimed is:
 1. An apparatus comprising: a steerable accesssheath having a proximal end and a distal end; a tip at the distal end;and a suction conduit positioned within a central lumen of the steerableaccess sheath from the distal end to the proximal end, the steerableaccess sheath containing an outer lumen surrounding the central lumenwith one or more channels therethrough, an outer circumference of theouter lumen and an outer circumference of the central lumen formingconcentric circles, the steerable access sheath further comprising aradiopaque material at the distal end or along a length of the steerableaccess sheath to enable tracking with a remote fluoroscopic device. 2.The apparatus of claim 1 wherein the tip further comprises a chamferedand soft edge for ease of insertion.
 3. The apparatus of claim 2 whereinthe chamfered edge comprises a restricted opening.
 4. The apparatus ofclaim 1 wherein the suction conduit is tapered with decreasing diametersfrom the proximal end to the distal end of the steerable access sheath.5. The apparatus of claim 1 wherein the suction conduit is configured togenerate turbulence.
 6. The apparatus of claim 1 wherein the suctionconduit is configured to enable alternating a direction of fluid flow.7. The apparatus of claim 1 further comprising a fluid inflow channelpositioned within the steerable access sheath from the distal end to theproximal end.
 8. The apparatus of claim 8 wherein the fluid inflowchannel is configured to collapse when there is no fluid inflow.
 9. Theapparatus of claim 1 wherein the tip is selectively deflectable toenable specific placement of the suction conduit.
 10. The apparatus ofclaim 1 wherein the suction conduit comprises a steering mechanismselected from the group consisting of one or more cables and a lockablecontrol actuator.
 11. The apparatus of claim 1 wherein the steerableaccess sheath further comprises an anchoring mechanism to prevent amigration of the steerable access sheath during active suction.
 12. Theapparatus of claim 11 wherein the anchoring mechanism is a fluid inflowchannel.
 13. The apparatus of claim 11 wherein the anchoring mechanismis positioned along a length of the steerable access sheath.
 14. Theapparatus of claim 11 wherein the anchoring mechanism is selected fromthe group consisting of an inflation balloon and one or more retractabletines.
 15. The apparatus of claim 1 wherein the suction conduitcomprises a clear section to enable visual confirmation of continuedsand and fragment removal.
 16. The apparatus of claim 1 wherein theclear section comprises a chamber having a particle filter to enablequantification and collection of sand and fragments.
 17. The apparatusof claim 1 wherein the suction conduit comprises a port sealed around anintroducer configured to agitate the suction conduit.
 18. The apparatusof claim 1 further comprising: a channel positioned within the outerlumen of the steerable access sheath from the distal end to the proximalend; and one or more fiberoptic imaging fibers positioned within alength of the lumen.
 19. An apparatus comprising: an access sheathhaving a proximal end and a distal end; a tip at the distal end; and asuction conduit positioned within a central lumen of the access sheathfrom the distal end to the proximal end, the access sheath containing anouter lumen surrounding the central lumen with one or more channelstherethrough, the access sheath further comprising a radiopaque materialat the distal end or along a length of the access sheath to enabletracking with a remote fluoroscopic device, wherein the suction conduitcomprises at least half the volume of the access sheath.
 20. Anapparatus comprising: an access sheath having a proximal end and adistal end; a tip at the distal end; and a suction conduit positionedwithin a central lumen of the access sheath from the distal end to theproximal end, the access sheath containing an outer lumen surroundingthe central lumen with one or more channels therethrough, the accesssheath further comprising a radiopaque material at the distal end oralong a length of the access sheath to enable tracking with a remotefluoroscopic device, wherein the access sheath has a preformed tipangle.